The technique of integrated circuit (IC) burn-in is applied industry-wide with the assumption that burned-in ICs have a much lower failure rate during operating life than ICs which are not burned-in. Several years ago this approach was valid for all ICs, but today burn-in procedures for some ICs provide little, if any, benefit. However, some customers still request burned-in ICs, assuming that thi...
View full abstract»

This paper develops a reliability model for a paged memory system wherein the pages of memory are physically distributed among several arrays of memory chips. Any of the available pages can be used to satisfy the required memory capacity. This paper also develops a reliability model for a page or block of memory words imbedded in an array. The model assumes that memory chips have failure modes tha...
View full abstract»

A software diagnostic that eliminates 2-bit and some 3-bit errors is described. The diagnostic procedure tests memory for errors that cannot be corrected by ECC (error correcting code): single error correct, double error detect. When an uncorrectable error is found, the diagnostic attempts to reduce it to a I-bit error. This is done either by reconfiguring the memory to distribute failing bits acr...
View full abstract»

Many software reliability growth models have been proposed in the past decade. Those models tacitly assume that testing-effort expenditures are constant throughout software testing. This paper develops realistic software reliability growth models incorporating the effect of testing-effort. The software error detection phenomenon in software testing is modeled by a nonhomogeneous Poisson process. T...
View full abstract»

This paper discusses the design and implementation of PolyChain, a FORTRAN program for reliability evaluation of undirected networks of a special structure via polygon-to-chain reductions. Theoretical results presented by Satyanarayana & Wood are reviewed. The program's design and its implementation in FORTRAN are described. A small problem is tested illustrating the code's output. Several large p...
View full abstract»

Kapur formulated quadratic programming problems for determining bounds on the design reliability, given some bounds on the probabilities of the stress and strength random variables. We modify Kapur's formulation to improve its accuracy, and present a solution to the resulting quadratic programming problems that can be evaluated manually.
View full abstract»

This paper presents a method for calculating the reliability of a system depicted by a reliability block diagram, with identically distributed components, in the presence of common-cause failures. To represent common-cause failures, we use the Marshall & Olkin formulation of the multivariate exponential distribution. That is, the components are subject to failure by Poisson failure processes that ...
View full abstract»

An algorithm is presented to find source-to-K-terminal reliability in a directed graph with independent arc failures. The algorithm is based on a discrete-time Markov chain with two absorbing states. The Markov chain has an upper triangular transition probability matrix, thus the probability of absorption in a state can be found by back-substitution. We show: 1) The source-to-K-terminal reliabilit...
View full abstract»

This paper presents a combined optimization/reliability technique to evaluate the reliability of large power systems. It uses Monte Carlo simulation for the individual operation/failure random performance of elements of a power network. This simulation overcomes the difficulty in constructing the many possible states for large power systems of complex topology. A simplified power-flow representati...
View full abstract»

Practical papers - computer programs

PAFT F77, a program for the analysis of fault trees, is coded in Fortran 77. Given the structure of a fault tree and the probability or failure rates of its basic events, PAFT F77 calculates the probabilities of the top and all intermediate events, as well as the marginal importance of all basic events. When the input is in terms of failure rates instead of probabilities, the marginal occurrence r...
View full abstract»

In current fault-tree analysis of systems, the usual algorithms for evaluation of fault-trees with repeated events apply the method of minimal cuts. Since the number of minimal cuts increases exponentially with the number of system components, truncation as well as optimization techniques have to be performed for the evaluation of large fault-trees. This paper presents an algorithm which combines ...
View full abstract»